Patentable/Patents/US-7542245
US-7542245

Composite thin-film magnetic head with non-magnetic conductive layer to balance parasitic capacitances

PublishedJune 2, 2009
Assigneenot available in USPTO data we have
Inventorsnot available in USPTO data we have
Technical Abstract

Composite thin-film magnetic head includes a substrate; a first insulation layer on the substrate; an MR read head element on the first insulation layer and provided with a lower shield layer, an upper shield layer and an MR layer with a sense current flowing perpendicular to a surface of the MR layer though the upper and lower shield layers; a second insulation layer on the MR read head element; an inductive write head element on the second insulation layer and provided with a lower magnetic pole layer, a recording gap layer, an upper magnetic pole layer with end portion opposed to an end portion of the lower magnetic pole layer through the recording gap layer and a write coil; and a nonmagnetic conductive layer electrically conducted with the lower shield layer and opposed to the substrate to increase the electrode area between the lower shield layer and the substrate.

Patent Claims
10 claims

Legal claims defining the scope of protection, as filed with the USPTO.

1

1. A composite thin-film magnetic head comprising: a substrate; a first insulation layer laminated on said substrate; a magnetoresistive effect read head element formed on said first insulation layer and provided with a lower shield layer, an upper shield layer and a magnetoresistive effect layer in which a sense current flows in a direction perpendicular to a surface of said magnetoresistive effect layer through said upper shield layer and said lower shield layer; a second insulation layer laminated on said magnetoresistive effect read head element; an inductive write head element formed on said second insulation layer and provided with a lower magnetic pole layer, a recording gap layer, an upper magnetic pole layer whose end portion is opposed to an end portion of said lower magnetic pole layer through said recording gap layer and a write coil; and a nonmagnetic conductive layer electrically connected with said lower shield layer and formed between said lower shield layer and said substrate in order to increase substantially a counter electrode area formed between said lower shield layer and said substrate, wherein a parasitic capacitance generated between said substrate and said lower shield layer is substantially equal to a parasitic capacitance generated between said upper shield layer and said lower magnetic pole layer.

2

2. The composite thin-film magnetic head as claimed in claim 1 , wherein said nonmagnetic conductive layer is laminated on a substrate-side surface of said lower shield layer.

3

3. The composite thin-film magnetic head as claimed in claim 1 , wherein a thickness of said second insulation layer is thinner than that of said first insulation layer.

4

4. The composite thin-film magnetic head as claimed in claim 1 , wherein an electrical resistance between said substrate and said lower magnetic pole layer is 100Ω or less.

5

5. The composite thin-film magnetic head as claimed in claim 1 , wherein said magnetoresistive effect read head element is a giant magnetoresistive effect read head element.

6

6. The composite thin-film magnetic head as claimed in claim 1 , wherein said magnetoresistive effect read head element is a tunnel magnetoresistive effect read head element.

7

7. A magnetic head assembly including a composite thin-film magnetic head and a support member for supporting said composite thin-film magnetic head, said composite thin-film magnetic head comprising: a substrate; a first insulation layer laminated on said substrate; a magnetoresistive effect read head element formed on said first insulation layer and provided with a lower shield layer, an upper shield layer and a magnetoresistive effect layer in which a sense current flows in a direction perpendicular to a surface of said magnetoresistive effect layer though said upper shield layer and said lower shield layer; a second insulation layer laminated on said magnetoresistive effect read head element; an inductive write head element formed on said second insulation layer and provided with a lower magnetic pole layer, a recording gap layer, an upper magnetic pole layer whose end portion is opposed to an end portion of said lower magnetic pole layer through said recording gap layer and a write coil; and a nonmagnetic conductive layer electrically connected with said lower shield layer and formed between said lower shield layer and said substrate in order to increase substantially a counter electrode area formed between said lower shield layer and said substrate, wherein a parasitic capacitance generated between said substrate and said lower shield layer is substantially equal to a parasitic capacitance generated between said upper shield layer and said lower magnetic pole layer.

8

8. The magnetic head assembly as claimed in claim 7 , wherein an electrical resistance between said substrate and said lower magnetic pole layer is 100Ω or less.

9

9. A magnetic disk drive apparatus including at least one magnetic disk, at least one composite thin-film magnetic head and at least one support member for supporting said at least one composite thin-film magnetic head, each composite thin-film magnetic head comprising: a substrate; a first insulation layer laminated on said substrate; a magnetoresistive effect read head element formed on said first insulation layer and provided with a lower shield layer, an upper shield layer and a magnetoresistive effect layer in which a sense current flows in a direction perpendicular to a surface of said magnetoresistive effect layer through said upper shield layer and said lower shield layer; a second insulation layer laminated on said magnetoresistive effect read head element; an inductive write head element formed on said second insulation layer and provided with a lower magnetic pole layer, a recording gap layer, an upper magnetic pole layer whose end portion is opposed to an end portion of said lower magnetic pole layer through said recording gap layer and a write coil; and a nonmagnetic conductive layer electrically connected with said lower shield layer and formed between said lower shield layer and said substrate in order to increase substantially a counter electrode area formed between said lower shield layer and said substrate, wherein a parasitic capacitance generated between said substrate and said lower shield layer is substantially equal to a parasitic capacitance generated between said upper shield layer and said lower magnetic pole layer.

10

10. The magnetic disk drive apparatus as claimed in claim 9 , wherein an electrical resistance between said substrate and said lower magnetic pole layer is 100Ω or less.

Classification Codes (CPC)

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Patent Metadata

Filing Date

February 7, 2006

Publication Date

June 2, 2009

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Cite as: Patentable. “Composite thin-film magnetic head with non-magnetic conductive layer to balance parasitic capacitances” (US-7542245). https://patentable.app/patents/US-7542245

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Composite thin-film magnetic head with non-magnetic conductive layer to balance parasitic capacitances — Noriaki Kasahara | Patentable